Have fun playing and practicing your arithmetic skills! Math Sudoku (aka Mathdoku) puzzles are built on square grids of 4x4 up to 9x9 cells. To solve them, you must place numbers into the cells so that each row and column contains each of the digits from 1 up to the size of the puzzle. Unlike the traditional Sudoku puzzles, you are not given any starting digits. Instead, the puzzle is divided into domains (areas surrounded by a bold outline) containing from two up to four cells. Each domain contains a hint consisting of a number and one of the mathematical symbols + x - /. The number is the result of applying the mathematical operation represented by the symbol to the digits contained within the domain. Each puzzle has a unique solution.